Conventional art of this kind includes, for example, the working machine maintenance system disclosed in JP 7-166582 A. This conventional art features that, when a communication is made from an operator of a working machine to the effect that a trouble has occurred on the working machine, data stored in a controller of the working machine are automatically transmitted to a control station via a communication means such as radiocommunication or a telephone line in accordance with an instruction from the side of the control station.
As conventional art different from the foregoing, there is, for example, the machine malfunction monitoring system and method disclosed in JP 11-65645 A. This conventional art features that, when a malfunction is detected during operation of a machine such as a construction machine, data of the malfunction are automatically transmitted from the machine to a monitoring station at a remote location, in other words, a control station via a communication network.
The above-mentioned prior art are each designed such that upon occurrence of a malfunction on a working machine such as a construction machine, data of the malfunction are automatically transmitted to a control station arranged at a remote location. Accordingly, they are effective for repair work of the malfunctioned working machine. These conventional art are, however, intended specifically for the occurrence of a malfunction, and cannot be used for the communication of a message other than the malfunction, such as a desired message corresponding to a given situation, for example, when an urgent contact with a work administration center is desired to report the completion of work or to review a schedule of work in view of the weather or the like or when it is desired to take measures in advance of occurrence of a malfunction.
According to the above-described prior art, information on a malfunction is sent only to a control station which is managed by the maker of the working machine, and no communication means to a user is referred to. The message relating to the above-mentioned work, however, has to be promptly transmitted to a work administration center, for example, the owner or the like of the working machine rather than the maker.
With the foregoing problem in view, the present invention has as an object the provision of a communication system for working machines, which can communicate messages corresponding to given situations, especially desired messages to respective users from sites, where working machines are arranged, to their corresponding work administration centers at timings as needed by radiocommunication.